The cat body is either 90 percent butt or basically there is no butt. It's a paradox. Where dose the butt end and the back begin? Some questions go beyond what man was meant to know.
@futurebird
Perhaps we can answer this question by answering a different question? Namely: can butts be liquid? Because if not, then [Fardin 2014] implies that there is no cat butt.
[Fardin 2014] “On the Rheology of Cats,” Marc-Antoine Fardin, Rheology Bulletin, vol. 83, 2, July 2014, pp. 16-17 and 30.
https://www.watsu-paris.fr/app/download/5819802223/On+the+rheology+of+cats+-+Rheology+Bulletin+-+juillet+2014.pdf
@futurebird there's a "memorable" Rob Reiner monologue in a rather forgettable movie, "The Story of Us" about this wrt humans.
(this is not a recommendation)